EP3349685A1

EP3349685A1 - Functional biological patch for pelvic floor prolapse

Info

Publication number: EP3349685A1
Application number: EP16795167.2A
Authority: EP
Inventors: Danilo Dodero
Original assignee: Assut Europe SpA
Current assignee: Assut Europe SpA
Priority date: 2015-09-15
Filing date: 2016-09-13
Publication date: 2018-07-25
Also published as: ITUB20153642A1; WO2017046824A1

Abstract

The present invention concerns an innovative biological prosthesis (1) designed for Reconstructive Surgery of the Pelvic Floor allowing central and rear defect repair. The innovative prosthesis in made of biological material (for example bovine pericardium) and comprises a proximal edge (6), a distal edge (7), a preferential direction A from the proximal to the distal edge, and four flaps, two of them (5a, 5b) distributed symmetrically with respect to the direction A at the proximal edge (6) and two (3, 4) asymmetrically distally to the median line of the prosthesis. This combination of material and shape allows a three-dimensional positioning of the prosthesis during surgery, replacing the damaged tissues effectively and mitigating the side effects.

Description

FUNCTIONAL BIOLOGICAL PATCH FOR PELVIC FLOOR PROLAPSE

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DESCRIPTION Technical field of the invention

The present invention relates to an innovative biological prosthesis designed for the vaginal reconstructive central and posterior pelvic floor surgeries. The prosthesis is characterized by a combination of a material and a particular shape that makes it three-dimensionally positionable during surgery. The in-situ positioned prosthesis is replacing the damaged tissues and effectively mitigating the side effects, better than any prosthesis available today on the market.

Background

The female pelvic floor, which includes urinary, genital and digestive apparatus respectively with the bladder, uterus, vagina, rectum and anus, can suffer from various disorders and diseases. Among these, the prolapse (POP: PelvicOrganProlapse) is one of the most frequent since over 50% of women showed a pelvic support deficit, and in 15-20% of these cases there is a significant clinical symptom. Among the major urinary symptoms of POP it can be mentioned: the involuntary loss of urine, the need to urinate often (more than 8 times in 24 hours) in the absence of urinary tract infections, difficulty in emptying the bladder completely. The vaginal symptoms of the most common POPs are: the sense of weight due to the presence of prolapse, postpartum pain caused by lacerations or episiotomies, decreased sexual perception. At last, the major anorectal symptoms of POP are: involuntary leakage of gas and/or feces, fecal urgency, inability to coordinate pelvic floor muscle, anal and/or perineal pain. The risk factors most often considered in pelvic floor dysfunction are in general: age, sex, chronic internal pathologies such as obesity; there are then other general factors of congenital type related to biochemical alterations of collagen fibers. At last, we should consider acquired risk factors, that are factors related to previous obstetricians problems which have a significant role in the onset of the uro-gynecological problems. Today there are several available therapeutic possibilities which can be classified into: conservative, minimally invasive and surgical. With regard to the latter, in the last 20 years, thanks to the experience gained in the abdominal surgery, also in clinical practice of gynecologic surgery, both laparoscopic and vaginal, where prosthetic devices (mesh or patch) have been introduced and widely used, and the high availability and variety of synthetic materials has directed operators to a massive use of synthetic implants.

The surgical approaches to the pelvic reconstructive surgery of the POP were multiple either by using the laparoscopic one, or especially the vaginal one, which is preferable because of the lower invasiveness.

Since 2000 and until 2011 the synthetic implants have been used indiscriminately sometimes also causing a number of serious complications, which led the FDA (US Food and Drugs Administration) to issue a "Warning" to regulate the use allowing the use of synthetic material only in centers with proven experience and only in second surgeries. Several manufacturers (J & J, Tyco-Covidien, AMS etc.) fabricated synthetic meshes of various shapes suitable for transobturator and/or transperineal insertion, employing particular introducers (similar to large needles). The meshes were fixed to the uterine cervical ring or the utero-sacral ligament and through the arms of the prosthesis inserted bilaterally via transobturator and/or transperineal in order to suspend the uterine bowels ( "conservative surgery") together with the bladder and the rectum.

Subsequently the latest generation of synthetic mesh has been developed, made of soft PP (polypropylene) or better in PVDF (Polyvinylidene fluoride).

The shape of the synthetic mesh is different depending on their use: the front mesh typically have a shape similar to a bib with 4 arms and they are implanted in transobturator way, while the rear mesh have the normally a form a bib with 2 arms and they are inserted with the introducer via transperineal.

As previously explained the synthetic mesh in use today are mostly symmetrical with respect to the left and right side of the patient. Within the indiscriminate use of such implants, without adequate training of professionals and due to the fact that the shape of the prosthesis does not lead the correct positioning in the operative field there have been many postoperative problems. The complete symmetry of the prosthesis allows the surgeon to a kind of "blindly positioning" that amplifies the potential erosion and infection of synthetic implants.

What described above is also achieved with surgical techniques considered as "tension free" or without fixed anchor points.

In conclusion, after the first promising results, the post-operative long-period assessment reported in the clinical literature, based on years of experience and on a significant amount of cases, showed substantial opposition and problems related to the widespread use and standardized synthetic prosthetic symmetrical kits. The nature of the material and the shape, which normally guides the positioning, can cause serious adverse events, such as vaginal erosions, bleeding, infection, organ perforations and prosthesis migration in a significant percentage of cases.

In recent years there has been a change of the prosthetic market towards the use of organic materials ensuring, thanks to of their properties of biocompatibility, a clinical improved result compared to synthetic materials, in terms of security as minimization of adverse events. Nevertheless, although representing a potential solution for known contraindications of synthetic ones, the biological implants proposals on the market do not solve the problem with a significant percentage in terms of functional efficiency of the reconstruction. In other words, the biological implants on the market cannot ensure adequate reduction of recurrence rate observed in the front, center and/or rear surgery for correction of pelvic organs prolapse.

Recurrence of prolapse post POP prosthetic surgery varies from case to case and from surgical center to surgical center. The percentages of recurrence have a large variability (from 20% to 60%), attributable both to the fact that different organic materials are used and to the absence of a suitable shape which does not provide a correct and leaded positioning in the surgical fixation of the prosthesis on the more suitable anchor points. From a different point of view, regarding the choice of the biological material, it should be noted that, while the biocompatibility characteristics of a biological prosthesis does not vary according to the type of the source material (pericardium, dermis, intestinal submucosa or fetal dermis) and/or the technology employed for obtaining the patches (either in the case of cross-linked matrices and in the case of bioabsorbable matrices), they massively affect the mechanical behavior of the patch. The mechanical properties play a crucial role in terms of functional warranty of the device implanted mainly when the surgical technique is a "Suspensive" type.

Besides the ability to support, the "ideal" material should have, as far as possible, the same consistency, strength, elasticity of natural tissues. Biological materials based on collagen, obtained from animal tissues, have characteristics influenced primarily by the used source of biological material, and secondarily by the treatment that the material undergoes to be decellularized, eventually crosslinked and sterilized.

Summary of the invention

The technical problem posed and solved by the present invention is to provide an improved biological prosthesis for prolapse of the pelvic floor surgery that avoids the needs mentioned above. The proposed prosthesis not only allows to minimize adverse events arising from its application, but also helps the effectiveness of the functional reconstruction. A correct application of the prosthesis improves the "vaginal habitability" and reduces consistently the center and rear recurrence without distorting the axis of the vagina.

This problem is solved by biological prosthesis according to claim 1.

Preferred features of the present invention are object of the dependent claims.

The present invention concerns a new biological remodeling mesh bioactive in the process of cell regeneration. The mesh is produced from biological material, preferentially from bovine deantigenate pericardium not cross-linked, perforated (eventually with holes of different shapes and sizes) characterized in that to have a notch and four extremes (edges or flaps). This shape is giving to the patch a profile similar to an H foldable on a flap, allowing the patch to perform tension-free suspension of the vaginal vault in a three dimensions way. The technical effect described above is generated by the combination of the chosen biological material, the Chemical-Physical treatment and the selected shape, which makes the proposed implants able to correct in a long term safe and functional way the pelvic organ prolapse and vaginal vault prolapse after hysterectomy. The prosthesis is able to rebuild a deep vagina, not deviated, large and supple, restoring the full functionality of the organ.

The biological mesh is very important to increase the strength of the repaired fascia creating a native biological support and vaginal size.

The application of designed biological mesh provides 4 anchor points: 1. Caudal back edge which is fixed with a multifilament non-absorbable suture made of a braided wire.

2. Upper cranial edges which are fixed to the residual Mackenrodt ligament with a nonabsorbable multifilament suture made of a braided wire.

3. Front wide edge which is fixed to the perineal body with an absorbable knotless spiral suture made by an unidirectional barbed wire.

Thanks to its special shape the prosthesis object of the present invention is inserted intravaginally and anchored in the three dimensions assuming a shape similar to a butterfly ("BUTTERFLY 3-D"). The mesh is anchored to the right sacrospinous ligament (caudal and REAR IN LOW), the Mackenrodt ligament residues bilaterally (cranial and UPPER TOP) and the perineal body (FRONT FORWARD).

A first advantage of the invention given can be identified by the fact that the prosthesis is configured to be securely anchored in the three dimensions of space defining the most suitable floor to function as a support.

A second advantage lies in the fact that the anatomical part which exerts a greater pressure on the discharge goes to "newly formed band" induced by the mesh and, having as a point of sturdy and durable anchoring the right sacrospinous ligament with a distribution of forces in the three directions, reduces the possibility of sagging and then relapse.

A further advantage is linked to the type of material because the biological material is inducing cell growth that determines the optimal proliferation of resistant and elastic collagen that responds to the needs of "vaginal interior space" and "prevention of central and rear relapses". Other advantages, features and the ways of implant of the present invention will become clear from the following detailed description of some embodiments thereof, given as example not in limiting way. Reference will be made to the figures of the accompanying drawings, in which:

· Fig. 1 shows the prosthesis in accordance with an embodiment of the present invention;

• Fig. 2 a, b, c shows an enlarged view of the proximal portion 6 in some possible embodiments of the spacing S;

• Fig. 3 a, b shows an enlarged view of the distal portion 7 in some possible embodiments of the spacing D; • Fig. 4 shows the prosthesis 1 configured as three-dimensionally is placed during surgery;

• Fig. 5 illustrates a preferred configuration of the prosthesis 1 with beveled edges;

· Fig. 6 (surgical procedure): detection of residues of the Mackenrodt ligaments bilaterally;

• Fig. 7 (surgical procedure): anchorage of biological Butterfly 3D mesh to residual Mackenrodt ligaments;

• Fig. 8 and Fig. 9 (surgical procedure): back colporrhaphy vaginal plastic colpoperineoplasty according to Kovac with a prior ligation of biological mesh to the right sacro-spinous ligament and to the perineal body.

Fig. 1 shows a prosthesis for the surgery of the central and rear pelvic floor 1 consiststing of organic material and having a preferential direction from a proximal end 6 to a distal end 7 along a preferential direction A.

The proximal-distal definition is carried out, in this description, depending on the positioning of the prosthesis on the patient by referring to the position of the Surgeon performing the surgical intravaginal operation. The positioning of the prosthesis in the body will follow the anatomical needs of the body in a three-dimensional shape as is illustrated in Fig. 4.

The prosthesis is constituted by two flaps (edges) in the distal position and two flaps (edges) in proximal position. The proximal end 6 has two flaps 5a and 5b in a symmetrical position with respect to the direction A separated by a spacing S. The distal end 7 is constituted by two flaps 3 and 4 asymmetric with respect to the direction A and separated by a spacing D. In the intermediate portion between the proximal end 6 and the distal end 7 is located the central portion 2 of the prosthesis which develops transversally to the direction A in the part where the spacings S and D are not present.

The spacing S is symmetrical with respect to the direction A and can be of various shapes such as rectangular, rectangular with lobes, semi-circular as shown in explicative but not restrictive way in Fig. 2. The spacing D is instead in an asymmetric position with respect to the direction A and has an elongated shape along the direction A as shown in explicative but not restrictive way in Fig. 3. The spacing D preferentially can be aligned with the end 5a of the spacing S along the direction of A. The spacing S is configured to be arranged and fixed below the bladder by superimposing and fixing through a surgical suture the extreme right and left of the proximal portion of the prosthesis so as to form a hole (opening) 8 at the center, whose final shape depends on the shape the spacing S; this hole will be located on a plane substantially orthogonal to the plane of the central portion 2 of the prosthesis, as shown in Fig. 4.

In a favorite configuration of the present invention illustrated in Fig. 2b the spacing S is configured in such a way as to generate, once the overlapping flaps 5a and 5b is complete, a hole 8 of roughly circular shape.

The spacing D is configured to allow placement of the prosthesis beside and above the restored Denonvilliers' fascia. In particular, the edge 3 is beside of Denonvillieres' fascia having the function to keep the mesh anchored to the right sacrospinous ligament and consequently acting in a three-dimensional way (BUTTERFLY 3 D) on the Vaginal vault prolapse (in case of vault prolapse) or rather the vaginal vault in case of vaginal hysterectomy (in case of complete vaginal vault prolapse). While the edge 4 will be above the Denonvillieres band and fixed to the perineal body, having the function to repair the rear compartment, hold the rectum and make the mesh solidal.

Preferably the spacing D has an elongated triangular shape along the preferred direction of the prosthesis A. Even more preferentially the spacing D can be characterized in its most proximal portion 8 by reinforcing elements so as to reduce the risk of breakage from tearing due to traction in opposite directions of the edges 3 and 4 of the prosthesis. In another version the proximal portion 8 of the spacing D can be circular as shown in Fig. 3b in order to cut out preferential breaking direction instead present in the sharp version of portion 8.

Preferably, the prosthesis has a dimension along the direction A of 8 cm and 6 cm along the direction perpendicular to A. In a preferred configuration, the spacing S has a maximum size along the direction A of 3 cm and 2 cm in the perpendicular and/or the spacing D has a maximum size along the direction A of 3.5 cm and 0.5 cm in perpendicular to A.

In even more preferred configuration the central portion 2 has a dimension along the direction A of 1.5 cm while the flaps 5a and 5b have a size in the direction perpendicular to A 2 cm, whereas 3 and 4 are respectively of 1.5 and 4 cm. Preferentially the prosthesis may have blunted outward facing edges.

Even more preferentially the chamfered edges can be formed with a curvature radius of V2 / 2 cm as shown in Fig. 5.

In this description, the thickness of the prosthesis in not mentioned at all since these are normally on the market with a thickness of 0,3-0,8 mm and therefore much less than the other dimensions of the prosthesis.

The prosthesis of the present invention can be applied according to a new and innovative surgical method which allows a greater depth and habitability of the vagina allowing the correction of DeLancey's level I and III. This method greatly reduces the risk of recurrence and side effects due to erosion that occur with synthetic prosthetic techniques.

The surgery is performed on the basis of classical principles of vaginal surgery with recent changes and through the use of new methods and surgical systems. The solution used for the "personal" preoperative infiltration consists of 6 vials containing 5 units of oxytocin, 2 vials of Naropin diluted in 100 mL of normal saline. The solution is injected into the vaginal chorion under the mucosa and over the of Halban's and Denonvillieres's fasce. This is followed by longitudinal colporrhaphy. It is preferred the use of bipolar scissors to make all the necessary cleavages possibly bloodless according to the usual surgical technique for the colpohysterectomy with front and rear plastic. After that a longitudinal colpotomy is performed on the median line followed by a diamond shaped incision of the perineum. The vaginal epithelium is carefully identified and separated from the rectum wall. The pararectal area is bilaterally prepared by dissection allowing the mobilization of the rectum from its lateral connections. After introducing a finger into the rectum, you can better assess the size and the level of the fascial defect in order to make a better repair. After fixing with an Allis' clamp the rectovaginal fascia suture are placed to close the defect and to anchor the rectovaginal fascia to the perineal body. During this suturing a finger inside the rectum allows the Surgeon to verify the presence of any issues of the suture in the rectal mucosa. The technique involves the fixation of the prosthesis to the anchoring points by braided not absorbable wires USP 2/0 gauge (EP 3). The anchoring points where the biological mesh is fixed are:

1. Right sacrospinous ligament; 2. bilaterally on Mackenrodt's Ligaments;

3. Perineal Body;

The technique includes dissection of right paravaginal space, identification of the right ischial spine and visualization of the sacrospinous ligament.

Employing a suture non-absorbable wire USP 2-0 a double-stitched suture is inserted through the ligament. Both ends of the suture are left unconnected and preserved to be attached to the edge 4 of the prosthesis. In the described technique any direct connection between the ligament and vaginal vault is intentionally avoided. The next step involves the recognition of the cardinal ligaments that are generally present as residues or parts of vaginal chorion on each paracervical side. Cardinal ligaments are grasped by Allis' clamps and then sutured with non-absorbable USP 2/0 (EP 3) wire to the ends 5a and 5b of the prosthesis. As soon as all anchoring points are located and exposed for connection of the prosthesis, it is placed in situ. The four arms of the prosthesis can be linked as follows: the lower right 4 to sacrospinous ligament, the two upper side arms 5a and 5b to the cardinal ligaments and the left lower arm 3 is sutured to the perineal body.

Subsequently the procedure is completed with the cosmetic repair of the perineum.

In a preferred form of technical realization, some sutures may be carried out in a continuous knotless manner using unidirectional barbed sutures.

Claims

1. Prostheses for the surgery of the pelvic floor 1 in biological material having a preferential direction from a first edge proximal 6 to a second distal 7 along a direction A and comprising two flaps 5a and 5b on the edge 6 and two flaps 3 and 4 on to the edge 7, characterized in that the flaps on the edge 6 are symmetrical with respect to the direction A and the flaps on the edge 7 are asymmetrical with respect to the direction A.

2. Prosthesis for surgery of the pelvic floor 1 according to claim 1, wherein the proximal edge 6 is formed transversely by two flaps 5a and 5b and between them a spacing S having the same dimension in the direction perpendicular to A.

3. Prosthesis for surgery of the pelvic floor 1 according to claim 1, wherein the distal edge 7 includes transversely the flap 4 larger than the flap 3 separated by the spacing D.

4. Prosthesis for surgery of the pelvic floor 1 according to claim 1, wherein the proximal end 6 is constituted by a spacing S shaped such as to generate a pseudo-circular shape hole in a plane approximately perpendicular to the plane of the central part 2 of the prosthesis when the left side and the right side of the proximal end 6 are superimposed.

5. Prosthesis for surgery of the pelvic floor 1 according to claim 1, wherein the distal edge 7 includes a triangular spacing D.

6. Prosthesis for surgery of the pelvic floor 1 according to claim 1, wherein the distal edge 7 includes a spacing D positioned along the direction perpendicular to the preferential direction

A in parallel position to the extreme 5a of the spacing S.

7. Prosthesis for surgery of the pelvic floor 1 according to claim 1, wherein the distal edge 7 includes a spacing D having a maximum dimension along the direction perpendicular to the preferential direction A of 0.5 cm.

8. Prosthesis for surgery of the pelvic floor 1 according to claim 1, wherein the distal edge 7 includes an elongated triangular shape spacing D in which the extremity most proximal 8 has reinforcing elements to avoid lacerations from tearing.

9. Prosthesis for surgery of the pelvic floor 1 according to any of the preceding claims having a length along the preferential direction A of 8 cm.

10. Prosthesis for surgery of the pelvic floor 1 according to any of the preceding claims having a length along the direction perpendicular to the preferential direction A of 6 cm.

11. Prosthesis for surgery of the pelvic floor 1 according to any of the preceding claims having flaps 3, 4, 5a and 5b, characterized by a maximum size along the direction perpendicular to the preferential direction A respectively of 1.5, 4, 2 and 2 cm.